According to high-frequency operations of electronic apparatuses, capacitors used in the apparatuses have been required to have excellent impedance characteristics in high frequencies. For this requirement, solid electrolytic capacitors including solid electrolytes made of conductive polymer having large conductivities.
FIG. 22 is a perspective view of conventional solid electrolytic capacitor 1100 disclosed in Japanese Patent Laid-Open Publication No. 2000-340463. FIG. 23 is a perspective view of capacitor 1100. FIG. 24 is a perspective view of capacitor element 1030 of capacitor 1100.
As shown in FIG. 24, in capacitor element 1030, a surface of anode body 1031 made of valve metal, such as aluminum foil, is anodized to provide a dielectric oxide layer, and is divided into cathode portion 1034 and anode portion 1033 with resist 1032 having an insulating property. Solid electrolyte layer 1035 is formed on a surface of cathode portion 1034. Cathode layer 1036 made of carbon and silver paste is formed on solid electrolyte layer 1035.
Anode portion 1033 of capacitor element 1030 is placed on a connecting surface of anode terminal 1037, and cathode layer 1036 is placed on a connecting surface of cathode terminal 1038. Connecting portions 1037A of the connecting surface of anode terminal 1037 are folded and joined to anode portion 1033 by resistance welding. Cathode layer 1036 is connected to the connecting surface of cathode terminal 1038 with conductive silver paste. Guides 1038A are formed by bending portions of the connecting surface of cathode terminal 1038.
Insulating resin package 1039 accommodates capacitor element 1030, anode terminal 1037 connected to the element, and cathode terminal 1038 connected to the element to allow anode terminal 1037 and cathode terminal 1038 to have respective portions exposing to the outside. The portions of anode terminal 1037 and cathode terminal 1038 exposing to the outside of resin package 1039 are bent along respective sides to the bottom of resin package 1039, thus providing outer terminals 1037B and 1038B, respectively.
In conventional solid electrolytic capacitor 1100, anode terminal 1037 and cathode terminal 1038 have complex structures, thus being a factor raising a cost. Further, anode terminal 1037 and cathode terminal 1038 have considerable lengths from anode portion 1033 and cathode portion 1034 of capacitor element 1030 to outer terminals 1037B and 1038B, thus providing solid electrolytic capacitor 1100 with a large equivalent series inductance (ESL) and a large equivalent series resistance (ESR). They prevent the capacitor from being used around a CPU of a personal computer, which requires a small ESL, a large noise suppressing performance, and an excellent transient response to deal with high frequencies.